ZYGOMYCETES 



345 



this •order the whole group may be looked upon as a lateral branch 

 of the Mucorini or Ancylistese successively modified (degraded) by 

 aquatic parasitism, with its extremity represented by the Synchytrieae, 

 Woronina (Cornu), and Rozella (Cornu). De Bary also discusses {loc. 

 at.) the suggested relationship to such algge as Protococcaceae, Cha- 

 racium, Chlorochytrium, &c. Apart from the possession of chlorophyll, 

 the conjugation of zoospores in these algae separates them from the 

 Chytridiace^, in which group such a process has not (at least as yet) been 

 discovered. Granting a relationship of the simpler Chytridiaceae with 

 Protococcaceae, &c., these might be regarded as leading up to Rhizidieae, 

 Ancylisteae, and Mucorini ; unless one regards the Chytridiaceae as com- 

 posed of two distinct sub-groups, Rhizidieae and Cladochytriese, related 

 to Mucorini and Ancylisteae ; and the Olpidieae and Synchytrieae to 

 Protococcaceae, &c. Only further research may determine these ques- 

 tions of affinity. 



Sub-order i : Rhizidie.e. — The life-history of Polyphagus Euglenae 



Fig. 297. — Polyphao2is Euglena Now. A , zoospore with drop of fatty matter and nucleus. B, young 

 plant attached to resting Euglena, e. C, zoosporange containing spores resting on empty pro- 

 zoosporange, a. D, conjugation : a, the receptive individual ; b, the supplying individual ; ^. the 

 swollen end of conjugation tube (rudiment of re^ting-spore) ; e, e, e, the Euglenae. E, portion of 

 D five and a half hours later : b, empty, s, mature^ represent the same parts as in D. {A x 550, 

 B, D, E, X 350, C X about 400.) (After Nowakowski.) 



(Nowak.), described by Nowakowski, furnishes us with the most highly 

 developed type of the whole group. The mycele consists of very slender 

 branching rhizoids, tapering each to a very thin point, and attaching 

 themselves to the Euglena-hosts. The original germinating zoospore 



